Daniel Mainwaring (aka Geoffrey Homes) (July 22, 1902 – January 31, 1977) was an American novelist and screenwriter. A native of Oakland, California, he began his professional career as a journalist for the San Francisco Chronicle and enjoyed a successful career as a mystery novelist (under the name Geoffrey Homes). He worked as a film publicist and eventually abandoned fiction for a successful career as a screenwriter. His first novel (and the only one he ever published under his own name), One Against the Earth